VPN server-tunnel mode on windows XP

Archived from groups: microsoft.public.windowsxp.security_admin (More info?)

Hello everyone,

I am trying to setup a windows xp machine as a vpn server that accepts
multiple ipsec tunnels from other windows xp machines.

My restrictions are the following:

1- I need to set the vpn server on windows XP (not windows 2000 server, nor
2003, nor ISA server, etc.)

2- I need to use tunnel mode ipsec

3- The vpn server should accept MULTIPLE vpn tunnels.

The first problem I faced is that windows xp does not support ipsec tunnel
mode between 2 xp machines. It only supports transport mode which is not what
I want.
To overcome this lack of IP tunneling I tried to use the built-in tunneling
capabilities such as PPTP and L2TP/ipsec, and it worked. But the problem here
is that a windows xp can not accept more than ONE SINGLE incoming connection
at a time, and I need multiple connections.

I think the solution could be one of the following:

1-Installing a third party FREE vpn server (or L2TP server) on windows XP.
If you know one please tell me.

2-Importing some features or packages from windows 2000 server or 2003
server to xp (i.e. some executables or services or plugins that enable xp to
run as a vpn server and accept multiple connections). If you know what to
import please tell me.

3- Installing a pure IP tunneling solution on windows xp so that it can be
combined with ipsec encryption to yield tunnel mode encryption.

I appreciate any help,

Alaadin